High molecular weight halogenated organic compounds and method of preparing same



Patented Nov. 28, 1939 mrso STATES P OFFICE HIGH MOLECULAR WEIGHT HALOGENATED ORGANIC COMPOUNDS AND METHOD OF PREPARING SAME ware No Drawing. Application October 20, 1937,

Serial No. 170,120 I 19 Claims. (01. 260 -94) This invention relates to high molecular weight halogenated organic compounds and methods of preparing same. More particularly, it relates to the halogenation of high molecular weight hydrocarbon polymers such as those produced by the polymerization of isobutylene at low temperature, generally below C. and preferably as low as -l0, 20 C., or even 80 C., in the presence of boron fluoride or other halide polymerizing catalyst efiective at such low temperature. This application is a continuation-in-part of Serial No. 749,072, filed October 19, 1934.

It has been discovered that such polymers, which may range from 1,000 or so up to 15,000, 20,000 or even 250,000 or more in molecular weight (determined by the viscosity method described in Staudingers Book, "Die Hochmolekularen Organischem Verdindungen, H. Staudinger Berlin 1932 Verlag Von Julius Stringer, page 56), are very stable and relatively inert chemical compounds, being substantially completely saturated with respect to hydrogen and having a very low iodine number, e. g. about 7 or less. Generally, the higher the molecular weight the more chemically inert 'are' these polymers. For instance, they are substantially not afiected by sulfuric acid and they are very resistant to oxidation, sulfurization, and many other chemical treatments. They difier from rubber which is quite unsaturated in that they cannot be vulcanized by sulfur while rubber can, and in that they are soluble in all proportions in petroleum hydrocarbons, such as naphtha, kerosene and lubricating oils, causing an increase in the true viscosity and viscosity index thereof, while rubber forms a gel (merely swells) in those liquids.

Other similar materials which may be treated according to this invention include any similar substantially saturated high molecular weight polymers which may be considered to have a chemical structure corresponding to that of a very long chain of carbon atoms containing occasional side chains of alkyl groups, such as methyl, ethyl, etc. Besides isobutylenes, other iso-olefines, such as iso-amylene, may be polymerized at low temperature, to produce high molecular weight polymers for use as raw material for "this invention. Although the above type of material is preferred, other materials believed to have a substantially similar chemical structure but formed in other ways may be used in some instances, for example, hydro-rubber (which is produced by destructive hydrogenation of rubber and is entirely diiferent from the parent substance in its properties and behavior).

lution of the polymer.

in will not be too viscous for treatment with the halogen underthe conditions of treatment. The

halogen to be used may be any one of the four,

i. e. fluorine, chlorine, bromine or iodine, although chlorlne is the cheapest and most practical.

The halogenation may be carried out at room temperature or elevated temperature, such as up to 50 or 100 C., but should not be too high inasmuch as halogenation at an excessively high temperature will cause excessive breakdown of the molecular weightof the product. The halogenation may be carried out at atmospheric pressure or considerably higher pressures, such as to 50 or 100 atmospheres or more, especially when carrying out the reaction at low temperature. Iodine may be used as a catalyst. If desired, the halogenation may be carried out in the presence of peroxides, e. g. benzoyl peroxide, to direct the halogen atoms preferentially to the alpha (end) carbon atoms in hydrocarbon mole-. cules. The percent of halogen incorporated depends upon the duration of the treatment. Generally, it is desirable to incorporate from 10% to 20% of halogen, although as little as 1% and as much as 50% may be incorporated if desired.

Various methods may be used for treating the high molecular weight hydrocarbon with the halogen. For example, chlorine may be bubbled through a carbon tetrachloride solution of the high molecular weight polymer or chlorine may be subjected to a countercurrent spray of a so- Another alternative is to carry out the halogenation treatment in the presence of bases, e. g. calcium or magnesium oxides or carbonates, sodium carbonate or bicarbonate, etc., or over water containing an insoluble carbonate, such as calcium carbonate or magnesium carbonate, for the purpose of absorbing hydrogen chloride liberated by the reaction.

If desired, instead of first preparing the polymer in relatively pure form and then dissolving it in a suitable solvent, such as carbon tetrachloride, and passing chlorine through this solution, the original polymerization of isobutylene for example, may be carried out in the presence of carbon tetrachloride or other solvent which will be suitable for the halogenation and then as soon -as the polymerization process is completed the solution of the high molecular weight polymer may be treated immediately with a desired halogen, thereby avoiding the removal of the solvent used during the polymerization step and subsequent redissolving of the polymer in a solvent for the halogenation step.

If desired, after the halogenation has been completed, the solution may be blown with air or inert gas, such as nitrogen or hydrogen, at a slightly elevated temperature, but preferablynot above 100 0., in order to remove hydrogen chloride. Anytraces still remaining may be removed by further blowifigtheliquid with ammonia, or other volatile amine, alone or mixed with air or inert gas, preferably at room temperature or perhaps up to or 0.

As an alternative, the product may be washed one or more times with dilute alkali, such as caustic soda, in order to remove any free hydrogen chloride remaining as a result of the halo gen treatment. It may also, under some circumstances, be desirable to heat the chlorinated polymer at a low temperature with a basic material, such as alcoholic potash, aqueous calcium hydroxide, sodium carbonate solution, sodium bicarbonate, etc., to remove one or possibly more halogen atoms and thereby produce a further stabilized product. compound, preferably an aromatic amine such as monoethyl aniline or methyl naphthyl amine, may be, added as a stabilizer (in proportions of 0.1 to 1% or so) to the finished halogenated hydrocarbon.

The products prepared according to the present invention are high molecular weight halogenated hydrocarbons and their physical properties depend upon the nature of the original material treated and the duration and type of treatment.

These products may be used for a wide variety of purposes; for instance, they may be condensed with aromatic hydrocarbons in the presence of aluminum chloride, boron fluoride or other condensing agents, to produce materials suitable as lubricants or blending agents in lubricants, such as pour depressors, or they may be used for any other type of condensation reactions in which halogenated aliphatic hydrocarbons are used as one of the reactants.

Halogenated hydrocarbon polymers, prepared according to the invention, may be used in conjunction with suitable soft resins and pigments,

withor without linseed oil, volatile solvents, etc., in the compounding of paints which are resistant to chemical and mechanical influences and also non-inflammable, or they may be compounded with various resins alone, such as those prepared from petroleum hydrocarbons by various known methods, in order to improve the properties of such resins.

Another field in which these high molecular weight halogenated polymers are useful is the preservation of wood by impregnation with wax. Ordinary wax-impregnated wood is subject to spotting by water but if a small amount, such as /2 to 10%, of. for instance, chlorinated polymerized isobutylene, containing 5 to 10% chlorine, is incorporated with the wax, the spotting of the impregnated wood is greatly reduced, if

A diflicultly volatile basic ular weight halogenated polymers may be mixed with an inert organic material of an oily or waxy nature, such as petroleum oil, petroleum jelly and paraffin wax, and the mixture added to solutions of artificial silk to be spun.

Many other uses will no doubt occur to those skilled in the art and it is an object of the present invention to claim broadly these high molecular weight halogenated products prepared from substantially saturated organic compounds having a structure represented by a long straight -chain of carbon atoms with a plurality of alkyl .side chains and containing a substantial proportion of halogen atoms incorporated according to this invention regardless of the purpose for which they are to be used.

The invention will be illustrated from the following examples:

Example 1 Chlorine gas is difiused at room temperature in ordinary diffused light, through a solution of carbon tetrachloride containing, dissolved therein, about 20% of a hydrocarbon polymer having a molecular weight of about 8,000 and prepared by polymerizing isobutylene at a temperature of 20 C. with boron fluoride as catalyst. When about 20% of chlorine has been combined chemically with the polymer the chlorination is stopped and the product is washed with water and the carbon tetrachloride removed by distillation.

The product of this experiment difiers from chlorinated rubber in that (1) rubber containing small amounts of chlorine is unstable, while the present product is relatively stable, (2) no solid chlorinated products were obtained as in the chlorination of rubber, and (3) the present product is miscible with paraflin wax while chlorinated rubber is not.

The chlorinated polymer, for example, ,may also be used in compounding high viscosity index extreme pressure lubricants either alone or in conjunction with sulfur or sulfur compounds or other materials known to the art in preparing extreme pressure lubricants.

The saturated high molecular weight polymers may also be mixed with wax, resins, mineral and vegetable oils, chloraromatics, esters, and the like, prior to or after halogenation. When blended in mineral oils, the chlorinated polymer may be used in conjunction with oxidation inhibiting amines, oiliness agents, thickeners, sludge dispersers, pour inhibitors, soaps, bright stocks, white oils, etc.

Example 2 When the isobutylene polymer is of a low molecular weight (around 3,000) the direct chlorination is eifected by passing chlorine gas through the polymer in the presence of very small amounts of iodine to catalyze the reaction. In this example no solvent is present and the resulting product requires only a slight carbonate washing to remove any of the remaining H01.

Example 3 Chlorine gas is passed under pressure through vents in the bottom of a tower packed with broken porcelain or spiral packing; when the tower has become saturated with the chlorine gas a solution of isobutylene polymer in carbon tetrachloride is sprayed in at the top of the tower passing down through the chlorine gas and being removed at the bottom of the tower and pumped back to the top of the same tower or other similar towers and the contact repeated until the chlorine content has reached the required amount.

The gaseous mixture removed at the top is scrubbed free of HCl by passing through solid caustic soda and again passed in at the bottom of the tower. The carbon tetrachloride solution of chlorinated isobutylene polymer is washed free of HCl by a slight carbonate washing and the carbon tetrachloride removed by distillation.

Example 4 150 grams of polymerized isobutylene (12,000 molecular weight) were dissolved in 850 grams of carbon tetrachloride by heating (120-140 F.) and stirring for 1 hours. After the polymerized isobutylene was completely dissolved, the

solution was transferred to a separatory flask and 0.5 gram of iodine added. Chlorine gas was passed through the solution at a slow rate at room temperature (75-80 F.) by means of a small alundum thimble attached to a glass tube and suspended close to the stopcock end of the separatory flask. Chlorine was passed through the solution for hours and then discontinued over night (about 16 hours.) Thefollowing morning the chlorine was again passed through the solution for eight hours, and then again shut 011. The chlorine saturated material was allowed to stand over the week end (60 hours).

A small sample (200 grams) of the carbon tetrachloride solution of the chlorinated product was placed in a filter flask, and the carbon tetrachloride distilled ofi at 200-210 F. (water bath) under laboratory vacuum pressure, after which carbon dioxide was blown through.

The product was a heavy viscous material, similar to the original polymerized isobutylene and having a slight pink color due to iodine present. The product shown by analysis to contain 24% chlorine was found to be completely soluble in petroleum ether and mineral lubricating oil.

In the removal of traces of carbon tetrachloride from the washed solution of chlorinated isobutylene polymer in carbon tetrachloride, almost the total amount of solvent is removed by mere distillation, either atmospheric or under reduced pressure, the remaining traces of solvent being removed by dissolving the practically solventfree chlorinated product in close cut naphtha with a boiling range close to the boiling point of carbon tetrachloride (76 C.) and redistilling.

Many of the above steps may be combined.

It is not intended that theinvention be limited to any of the specific examples given nor to any theories of the operation of the invention but in the appended claims it is intended to claim all inherent novelty in the invention as broadly as the prior art permits.

We claim:

1. High molecular weight halogenated organic compounds containing more than 1% of halogen; obtained by halogenation of a material consisting of a substantially saturated linear hydrocarbon polymer of the aliphatic series having a molecular weight in excess of about 1,000 and having a plurality of short alkyl side chains.

2. Product according to claim 1 obtained by halogenation of an iso-oleflne polymer.

3. Product consisting essentially of chlorine derivatives of polymerized isobutylene having a molecular weight above about 1,000, said product being soluble in mineral oils, miscible with paraffin wax and having a liquid to semi-solid consistency.

4. High molecular weight halogenated organic compounds derived by polymerizing isobutylene at a temperature below C. in the presence of a boron fluoride type catalyst to make a linear polymer having a molecular weight above about 1,000 and subsequently treating the resultant polymer with a halogen to incorporate a substantial amount of halogen therein.

5. Product according to claim 4 containing 5-35% of chlorine.

6. The process of preparing high molecular weight halogenated organic compounds, which comprises incorporating at least 1% of halogen in a substantially saturated aliphatic hydrocarbon having a molecular weight in excess of about 1,000 and having a chemical structure represented by a long straight chain of carbon atoms and containing a plurality of alkyl side chains.

7. Process according to claim 6, carried out at a temperature between the approximate limits of C. and 100 C. and at a pressure between the approximate limits of 1 and 100 atmospheres.

8. Process according to claim 6, carried out in the presence of a solvent for the high molecular weight hydrocarbon being treated.

9. Process according to claim 6, carried out in the presence of carbon tetrachloride.

10. The process of preparing high molecular weight halogenated organic compounds, which comprises polymerizing a material consisting essentially of isobutylene at a temperature below about l0 C. in the presence of boron fluoride as catalyst until a polymer is produced having a molecular weight between the approximate limits of 1,000 and 250,000 and treating said polymer with a halogen until a substantial proportion of halogen has been chemically combined into the hydrocarbon polymer.

11. Process according to claim 10, in which the isobutylene polymer is treated with chlorine in the presence of carbon tetrachloride until about 20% chlorine has been united chemically with the polymer.

12. Process according to claim 10 in which the isobutylene polymer is treated with chlorine in the presence of a small amount of iodine as catalyst.

13. Product consisting essentially of an isobutylene polymer having a molecular weight above about 2,000 in which has been incorporated at least about 1% of chlorine.

14. A new composition of matter comprising a synthetic solid plastic resin produced by chlorinating a solution in carbon tetrachloride of polymerized isobutylene having a high molecular weight.

15. As a new product, a solid chlorinated deriv ative of a plastic substantially saturated isobutylene polymer having a high molecular weight in excess of about 1000.

16. As a new product soluble in light petroleum hydrocarbons a halogenated derivative of a plastic substantially saturated isobutylene polymer 7 having a molecular weight in excess of about 1000, said halogenated derivative containing about 10% of chlorine.

1'7. A new composition of matter comprising a synthetic plastic resin having between 20 and 50% of chlorine stably combined with a high molecular weight polymer of isobutylene';

18. The process of making chlorine containing resins whichcomprises polymerizing liquidisobutylene at temperatures ranging from -l0 C. to 80 C. with boron fluoride catalyst, whereby it is converted into a high molecular weight hydrocarbon resin, separating the resulting resin from remaining boron fluoride and dissolving it in carbon tetrachloride solvent, subjecting said resin while in carbon tetrachloride solution to the action of chlorine until from 1% to 50% of chlorine is absorbed and thereafter removing the solvent from the chlorinated resin.

19. The p ocess of making chlorine containing resins whic comprises polymerizing isobutylene at a low temperature in the presence of a catalyst whereby a high molecular weight plastic substantially saturated hydrocarbon polymer is produced, chlorinating said polymer while in solution in a solvent until the resulting product contains from 1% to 50% of chlorine, part 01' said chlorine being in'hydrolyzable form, and thereafter treating the chlorinated product to remove hydrolyzable chlorine.

ARNOLD J. MORWAY. FLOYD L. LHLLER. 

